Have great traction on the rocks. Update: 11/14Their customer support actually replaced the unit right away. El armado es muy simple. I would expect sketcher sandals to last at least a year. Battery life is long, and they are easy to use once you put them in your ear properly. If you want them to snuggle your feet I would recommend you ordering 1/2 a size smaller. Not too afraid to drop them but they fit surprisingly well in the ear for no fins. This is my 1st helemet Bluetooth device. I can place four pairs on each of the four shelves and then four across the bottom underneath, so technically can fit 20 pairs of shoes. I attached some photos to my review to show how it pops out slightly.